One reason for diffrent collored mag plates is this .say you have one mag loaded with standars H.P.ammo and the one with the orange floor plate is loaded with fragnabule ammo like the pressed powdered copper ammo that will preform like a full metal jacketed round in flesh but will turn to dust if it hits sheetrock so it won't penatrate walls in a house .I mark my mags for my M-4 patrol carbine with a strip of red electrail tape that have
55gr V-MAX bullets in them for soft targets like humans the bullet will explode when it hits flesh and won't exit a person or a wall and don't mark my mags that have M855 ,55gr FMJ's in them .
I keep the marked mag in the gun because most of the time if I use the M-4 I'm clearing a building ,but have a mag with the FMJ's jungle cliped to it if I need to enguage a car or penatrate a bairrer/ car boby all I have to do is a quick mag swap ,rack the charging handle and now I have some penatration .Given the choice and time though If I'm shooting at a car I grab my M-1100 tactail that I keep loaded with a slug then a 00 buck ,slug ,buck ,so on .
Lou